div{background: #000; color:red; font-size: 40px; 
text-align: center;
font-weight: bold;
}

.header{width: 100%; height: 50px; margin-bottom:10px;}
.content{width: 100%; height: 400px;display: flex; margin-bottom:10px;background: #fff;}
.left{width: 150px; margin-right:10px;}
.con{ flex:1;}
.right{width:150px; margin-left:10px;}
.footer{width: 100%; height: 80px;}